The invention relates to an overpressure valve which is in the form of a one-way valve or a check valve and which comprises a pot-shaped housing with a base and central opening and which also comprises a valve seat which interacts with a spring-loaded closing body.
In various mechanical engineering applications in which individual parts or assemblies are exposed to a pressure from a medium, precautions must be taken so that limit loads are not exceeded in the pressure-loaded areas. In the state of the art, for protection from loads that are too high, it is known to use overpressure valves in hydraulic systems, wherein these valves open when a limiting pressure is reached and discharge a partial flow of the hydraulic fluid via a bypass or a discharge channel.
For example, for a hydraulic tensioning device of a traction mechanism drive, in particular, a chain drive, it is necessary to limit the medium pressure to prevent a load that is too high on the traction mechanism, in order to keep the friction and wear low. For reducing the pressure, overpressure valves are used. For example, in DE 41 33 560 A1 and U.S. Pat. No. 6,193,623, hydraulic tensioning devices are shown and described in which overpressure valves are used to prevent high tensioning pressures. Another tensioning device is disclosed in DE 600 27 227 T2 that relates to a hydraulic chain tensioning device that includes an overpressure valve. Here, in a flow path there is a stepped hole in which a ball is arranged that is pretensioned with a spring in the direction of the hole axis and can form a sealing contact on a sealing seat. If the pressure increases in a compression space, the media pressure acts on the spring-tensioned closing ball and attempts to press the ball against the spring force. If this pressure is high enough, i.e., the pressure difference in the adjacent compression spaces is sufficiently large and exceeds the spring force of the closing ball, then this leads to pressure equalization. If the pressure difference decreases, the spring presses the closing ball back against the sealing seat, forming a seal, wherein the overpressure valve closes.